I just started Orbx Central, it downladed the update V4.3.5. Using P3D V6. When I look at my installed airports, it says "Installed into an Orbx Library. XYZ is installed into Prepar3D V6"...
On top of Orbx Central it still says "Prepar3D V5".
@Douglas96
Did you try a location like Interlaken (Swiss), for instance? As I remember most noticable changes to the default mesh occur in mountainous areas, not those with moderate hills. Perhaps you expect more changes in areas that are depicted realistically by default mesh.
I got no problem with Global Ultimate in P3D V.3xx.